The main assembly of inertia crushers making their construction and operation rather complicated is the assembly of unbalanced mass drive of the inner cone. In this light, simplifying the abovementioned assembly is the main trend in the improvement of inertia crushers.
Known in the art is an inertia cone crusher comprising a housing having an outer cone and an inner cone having a spherical support and a shaft on which is installed a cylindrical bearing bush of an unbalanced mass member, the bush having a spherical end thrust bearing (cf. USSR Inventor's Certificate No. 481305, publ. 1975).
The spherical end thrust bearing of the bush is provided on the end of an intermediate shaft journalled in the housing by means of bearings and having a crank drive for transmitting rotation to the bush to which the unbalanced mass member is secured.
This construction is rather complicated owing to the provision of the intermediate shaft and the crank drive. In addition, the assembly of the unbalanced mass member system is difficult because it is necessary to couple the unbalanced mass member to the intermediate shaft in the interior of a crank case which is inaccessible for inspection.
Also known in the art is an inertia cone crusher compising a housing having an outer cone secured thereto, and inner cone mounted concentrically with the outer cone on a spherical support in the housing for rotation about its axis and gyratory motion relative to the axis of the outer cone, the inner cone having a shaft. A cylindrical bearing bush is installed on the inner cone shaft, the bush supporting an unbalanced mass member and being connected by means of a flexible link to a power drive. The inner cone shaft has at the free end thereof a bore in which is secured a spherical support of the bush carrying a spherical end thrust bearing engaging with its annular flat surface a pivot journal which is rigidly connected to the bottom wall of the bush by means of a central rod. For locking the position of the unbalanced mass system there are provided at least three hydraulic jacks in the bottom wall of the housing of the prior art crusher (cf. USSR Inventor's Certificate No. 1039555, publ. 1983).
In using the prior art cone crusher, the inner cone is dismantled (e.g. for replacing its wear plates) by uncoupling the shaft from the bush. For that purpose, the central rod is relieved from the mass of the bush and unblanced mass member by lifting the assembly by means of the jacks relative to the inner cone shaft. This facility, at the same time, provides for positioning the bush almost vertically. Then the rod shank clamp is released, the outer cone unscrewed, and the inner cone removed. The assembly is carried out in the reversed order. In doing this, it is necessary to make certain that the central rod is in the vertical position so as to be received in the bush bottom hole.
High labour consumption of the abovedescribed operations combines with the need to manipulate the clamp and jacks in a very restricted space since all these assemblies are accommodated under the crusher.
The need to have the clamp and jacks makes the crusher construction complicated.